Twitter is incredibly avoidable. Everything about it is likely faked and exaggerated. Revenue/profit for sure. Number of users for sure. Number of users that aren’t bots for sure too.
I use Twitter everyday because of my politics interest but it isn’t that popular any more (I know the supposed numbers say otherwise)
Whatsapp is probably the hardest to avoid for most people in parts of the world where it's dominant. The number of people who need to use Facebook or Twitter is likely much smaller, and very few of those need to install a native app instead of using the website.
They absolutely are not. No more than alcohol or tobacco addiction are de-facto unavoidable. And the people who are absolutely addicted to those platforms will always have the option of the web page no matter what you do to the app.
Some apps are de-facto unavoidable, like Facebook, Whatsapp and X.